Soldering iron



APH; 1851933 1 L. JONES SOLDERING IRON Filed Sept. 28, 1929 INVENTOR Lesner LJO u, AWN

ATTOR'N EYS Patented Apr. 1s, 1933 e Y 1,904,051

lUNITED STATES PATENT OFFICE LESTER L. JONES, F ORADELL, NEW JERSEY SOLDERING IRON Application filed September 28, 1929. Serial No. 395,800;

This invention relates to soldering irons plies to a soldering operation performed and more particularly to soldering irons upon large or heavy parts in Comparison Which are to be used relatively intermittent- With a soldering operation performed upon 1 light Wires or similar connections. An- I '5 It has long been a problem in using solderother illustration is in the alternate use of 55 ing irons to keep the point in good condition, solder and insulating or sealing Wax, as is that is to have it constantly coated With a often the case in the manufacture of small' continuous lilm of unoxidized solder. This electrical part-s. Some times a joint is sol- A problem is normally very acute Where the dered and is subsequently covered With insusoldering iron is used intermittently and on lating Wax, and at other times a unit, such 60' relatively small Work, asfor example, in eX- as a condenser, is first sealed Within a case perimental laboratories or in small scale proby means of wax, and leads therefrom are duction where the operator performs several subsequently soldered to terminals on the operations between the soldering operations. case. A loW temperature is desirable for I In such a case the solderingr iron point melting the wax relative to the higher tem- 65 corrodes and must be freshly prepared by perature needed for the soldering operation. cleaning or scraping in order to make a good The primary object of the present inven-` soldered joint. If the point is kept fairly tion is to overcome the foregoing difliculties,f

Cool the solder'vvill not oXidiZe and the'point and to provide a novel soldering iron strucr Will keep in good condition. This is, hovvture and a method for using the same which 7bAr` ever, very troublesome because it greatly Will make it possible to control the temperaincreases the length of time required for ture of the point or tip of the soldering iron soldering, and in some cases, where the metal Without necessarily similarly controlling the parts to be joined are large, entirely prevents temperature of the entire soldering iron'.

the proper fluxing of the solder. f This I accomplish, generally, by 'providing 75 f One method of avoiding this diliiculty, in a soldering iron comprising a heat retaining the case of an electric soldering iron, is to body of relatively large mass and a soldering use two degrees of heat selected by means of tip of relatively small mass,and controlling a snap switch or, in the case of an externally the temperature of the tip by varying the heated iron, to use two positionsin the flame, heat transfer between the heat retaining body 80 one of Which just heats the iron enough to and the tip. keep the solder on the point liquid, While the The temperature of the tip depends not other or higher heat position raises the temonly upon the heat transferred thereto from perature to the best value for soldering. the heat retaining body, but also upon the '35 This method is, however, wasteful of time heat radiated therefrom. Accordingly, an- 85v because of the fact that the Whole iron cools other object of the present invention'is to to the lower temperature, and when the highcontrol the heat radiation from the soldering er heat is employed an appreciable interval tip, and to make this radiation vary inthe of time is required to heat up the point. proper sense to advantageously cooperate 40 Therefore, unless the operator starts the iron with the applied variations in the heat trans- 90 heating a sulhciently long time before using fer from the heat retaining body to the tip. it, he must Waitbeforeliis soldering operation Another object of the present invention can begin. resides in the provision of a simple means for A` similar problem arises in other operaobtaining the desired variable heat transfer,

tions Where it also is desirable to have availand to this end I mount the soldering tipi` 95 able several optionally selectable temperareciprocably on, and preferably in a longitures at the tip of a soldering iron. For eX- tudinal bore in the heat retaining body. The ample, a dierent temperature is required for projection of the tip out of the body, and at soldering with hard solder than is desirable the same time the extent of insertion of the 5 for soldering With soft solder. The same apother end of the tip into the body, are tliere-` 100 fore simultaneously variable, and in the outward position the heat transfer from the body to the tip is reduced and the heat radiation from the tip is increased, whereas in the inward position the heat transfer from the body to the tip is increased and the heat radiation from the tip decreased. In this many ner a variable temperature may be obtained at the tipA of the soldering` iron even though the temperature of the heat retaining body is not similarly varied, and may even be oppositely varied.

Another object of .the present invention is to adapt such 'a temperature controllable'- soldering iron particularly for intermittentk soldering such as ywas previously described.

VTo this end the methodV ofy my invention includes reducing the heat transfer between the body and thetip by moving the tip out-.

Wardly from the body suciently to reduce the temperature of the Vtip to vthe melting point of solder in order to prevent oxidation of. the solder on the tip between soldering operations, andv further includes increasingVVV Y the heat transferbetween the body and thev tip by moving the tip into the body during soldering operations in order to rapidly heat the tip to the soldering temperature. At the` same time the radiation from the tip may be varied so that increased radiation is obtained between soldering operations and decreased radiation is obtained during soldering operations.

, ing'my invention. In such asolderin'g iron f theheat retaining body is heated in the cus-A tomary manner by a resistor, whichmay itself constitute a part of the heat retaining body, and myiinventionis applied rnerely by constantly heating'the'body by means of the resistor, and controlling or varying the temperature' of` thentip Vby'controlling the heat transfer to the tip andthe heat radiation from .the tip in the manner aforesaid. #Ob

Yviously,`with an iron embodying my yinventionl the temperatureof the tip depends upon and is established relative to the temperature Voftheheat retainingbody.V Inasmuch as the Y temperature of the heat retaining body is kept t substantially constant in the case of al soldering iron ofthe electrically heated type, it follows that the temperature .of thev tip may likewise be `kept constant for anyV given setting relative tothe heat retaining'body, so that my invention is particularly advantageously applicableto this ktype of iron, although it also is usefully applicable 'to asoldering iron of the externally heated type, and there avoids the necessity of accurately var-iably v positioning the iron in the'ame.

A still further object of the present invention is to so arrange the soldering iron vthat y Ving body when the soldering iron is not in use, preferably simply by so constructing` the iron that the heat radiation from the heat retaining body is reduced at the same time that the heat radiation from the tipis increased. rlf'hisl causes a rise inthe temperature of the heat retaining body until a new equilibrium temperature is reached, and this rise in temperature insures that the soldering tip will be very rapidly raised to thesoldering temperature when the tip is again inserted into thebody of the iron.V

To the accomplishment of the foregoing and such, other objects as kwill hereinafter apear, .my invention consists in the method and the soldering iron elements and their relation one to the other as hereinafter are more particularly described in the specificationand ksought to be deined in the claims. The specification isaccompanied bya drawing-in which: f y f Fig. l is a longitudinal section through a soldering iron embodying features of my in-' vention; and Fig. 2 is a section taken in the plane of the linefQe-.Q in Fig. l. Y

Referring tothe drawing, thesoldering iron consists generally `of avheat retaining body 2 of relatively large mass, and a soldering vpoint or vtip l of relatively small mass,

Ythe latterlbeing reciprocably mounted on and movable relatively to the body 2. rlhe reciprocation of the tip '4l is limited between an eXtreme kinward and an eXtreme outward po-` sition by stop means .6. The heat retaining body 2 is aiiixed to `and supported Vby aV heat insulatinghandle .8, withinwhich there is housed resilient means l0l urging thetip l to its outward position. lsIanually operable meansr 12 is arranged to retain the tip at anyy position' again'stthe pressure of the resilient Vmeans v10,-and is further arranged'to loclr the tip a in any :of one or more selected positions. The heat retaining body 2 may be externally heated, as by a gas flame, but in the present instance is illustrated as being electrically heated by a resistor or resistance coilv or winding 14 housed in a suitable annularV electrically insulated 4winding space within the heat retaining body r2.

Considering the illustrated soldering iron more in detail, it Awill be observed that the heat retainingbody VE2 is preferably provided with a longitudinal bore 20, While the tip 4 is most simply made .cylindrical rin shape n and-of proper diameter to be received by they bore 20. A. slot E22 maybe cuty alongV the 'tip 4; to define the limits or extent of movement of the tip 4 in cooperation with the stop means 6. l

The tip 4 is providedvwith a rearwardly extending shank 24, which, if desired, may be made of a poor heat conducting material, against which the compression spring 10 bears. The shank 24 is preferably tapered, as shown, while the resilient manually operable means 12 carries a projection 26 which in turn presses upon a ball 28, and the pressure of the latter against the tapered surface 24 holds the shank and the tip 4 against outward movement. By manually depressing finger piece 12 its pressure on the ball 28 may be relieved, and the tip 4 immediately moves outwardly under the influence of spring 10. A projection 30 may be provided upon the handle 8, against which the manually operable finger piece 12 may fulcrum when the pressure on ball 28 is being relieved.

F or locking the tip 4 against inward movement when the tool is being used the shank 24 is preferably provided with a hemi-spherical depression or recess 32, into which the ball 28 may set when the tip is forced into the iron the right distance. If desired, an additional recess 34 may be provided for holding the tip at an intermediate position in order to provide a lower soldering temperature than is obtainable when the tip 4 is inserted fully into the bodv 2 of the iron. The several temperatures obtainable may 'be selected for special operations, such as hard soldering, soft soldering, soldering of solid bodies, soldering of light connections, melting of Wax or insulation, and so on, `as well as the nonoxidation of solder between soldering operations.

Aside from the structural modifications necessitated by the movable elements needed for the practice of my invention, the iron may in other respects be conventional. a The resistance winding may be made of heavy resistance wire of great length, so that the winding itself constitutes a major portion of the heat retaining body, or it may be made of fine resistance wire housed within a separate heat retaining body, as in the case here shown. It may also be a carbon or like resistor, in which case the resistor may also constitute the heat retaining body. The precise construction of the heating element, of course, forms no part of my present inventio-n, and in the clailns which follow when I speak of the soldering iron as having a heat retaining body and a resistor I am considering the resistor in its dual function, first, as a part of the heat retaining mass, and second, as a heat generating electrical conductor. The handle 8 may be made of wood or molded composition having heat insulating properties, and the iron proper may be mounted in the handle by means of a tube 40, the space 42 being filled with a preferably electrical and heat insulating filling material, and being provided with grooves or slots 44, best shown in Fig. 2, through which the Wires 46 for the heating current may extend. The Wires 46 may be brought together into a single extension wire 48, passing through the end of the handle 8 in the usual manner.

The iron may be designed with still another consideration in view, namely, to make the heating of the tip 4 especially quick when about to solder by causing the internal temperature of theheat retaining body 2 to be raised between soldering operations. To this end the extension of the tip 4 within the body 2 may be made particularly short, the good heat conducting portion of the tip 4 terminating inthe present case just beyond the stop means 6, as is indicated at 5 on the drawing. This results in a considerably reduced dissipation of heat from the body 2, and the temperature thereof is raised until a new equilibrium temperature is established. The same result may be attained by permitting the tip 4 to extend further into the body 2, but at the 'same time making the material at the inner end thereof, as at 7, a poor heat conductor, such as iron. In consequence there is very little heat dissipated from the body 2 when the tip is extended, but there is a rapid heat transfer from the body 2 through the good heat conducting material at the forward portion of the tip 4 when the tip is inserted into the body.

In operation the tip 4 is pushed in by pressing the tip against the soldering iron stand, or against any other suitable object,`

which in some cases may be the object to be soldered. The locking means 12 retains the tip in its inward position against the force of the spring 10. lIn this position the tip is close to the resistor 14 and the heat retaining body 2, and only a small portion of the tip is exposed to the atmosphere for heat radiation, and consequently the temperature of the tip very quickly rises to the proper soldering temperature. This rise in temperature is almost instantaneous because of the fact that the main heat retaining body 2 is always at the proper high temperature, or even at a higher temperature, and therefore need not be raised in temperature, while the tip 4 is of relatively small mass and its telnperature is readily raised. f

When the soldering operation has been completed it is merely necessary to press the manually releasable locking means 12, whereupon the tip 4 is moved'to its outward position by the spring 10. Inthis position the heat transfer between the heat retaining body 2 and the tip 4 is greatly reduced, while the radiating surface of the tip 4 is greatly increased, and the tip extension is so adjusted that the resulting temperature is held sufficiently high to melt the solder but not sufiicientlyl high to oxidizeV the same. The rec without departing from the spirit ofr the in'- and aV heat retaining body, a soldering/tip vention, defined in the followingclaims. ,l claim: f n

1`. A soldering iron` comprising a: handle heated thereby and movably related thereto, and means located at the handlefor controlling the movement of thetip in order-to regulate the temperature -of the tip.

2. A solderingfiron comprising Va heatretaining body, a soldering tip reciprocably` mounted iny the body, and a manually operablemeans located at the handle of the solden ingV iron `for controlling the position of the tipin'the body in order to control the temperature of the tip. I i -j Y 3.k A soldering iron comprising a heat retaining body of relatively large mass, assoldering tip of relatively small mass one end of whichV is freely reciprocably mounted on thebody, resilient means urgingthe tip outwardly and means 'for retaininglthe Atip in any of a plurality of positions relative to the body in 'order to control the temperature of thetip.`

4. A soldering iron comprisingy a heat retaining body of relatively large mass, a sol-` dering tip of relatively small mass-one end of which is reciprocably inserted in the body, resilient means urging the tip outwardly from the body, and manually operable locking means for retaining the tip atrany. desired position within the body.

- 5. Asoldering iron comprising Va heat retaining body 1 having Ta Alongitudinal bore therein, a soldering tip reciprocablymounted in the bore of the body, resilient means urging the tip to an outward position, and manuallyireleasable locking means for locking the tip Aat an inward posit-ion.

6. A` solderingiron comprising a heat retaining body of relatively large masshaving a longitudinal bore therein, a soldering tip of relativelysmall mass reciprocablymounted in the bore of the body, stop means for limiting the reciprocation of the tip, resilent means urging the ti to an outward osition and manually releasable vlocking means for locking the tip at an inward position.

V7. An electric solde-ring iron comprisinga heatV retaining body, a resistor for heating theV same, a soldering tip reciprocablv mountedl in the body, a heat insulating vhandle fixed to the body, resilient means urging'the tip to 'anL outwardposition, and manually operable means forlocking theV tip at an'inward position.

8. An electric 'soldering iron comprisinga heat retaining body of relatively large mass, a resistor for heating the same, a soldering tip of relatively small mass reciprocably Vmounted in the body in order to make the projection of thev tip out of the body variable, stop means forlimiting the reciprocation of the tipa heat insulating handle fixed to the body, resilient means within the handle urging the tip to Van outward position, ,andVA manually releasable locking means for lockingthe tip atan inward position.

9. A soldering iron comprising a hollow heat retaining body 'of'relatively large mass,

an elongated soldering tip of relatively small l mass heated thereby and readily reciprocable therein, and mating stop means on'the tip and on the body for'positively limiting the free reciprocation of the tip betweenpredetermined inwardV and outward limits.

10. A soldering ironcomprising a hollow heat retaining body of relatively largemass, anelongated soldering tip of relatively sm all mass heated thereby and readily reciprocable therein', and mating stop means on the tip and on the body for positively limiting the yfree reoiprocation of thevtip between predetermined inward andn outward limits, the

heat transfer from the body 'to the tip in the n inward position being madesufiicient to rapidly heat the tip to the soldering tempera-- ture, and the heat transfer from the body to the tip in the outward position being adjustedito be'l only snflicient to keepfth'e temperature of the` tip at the melting point ofthe solder but'not to oXidize the same.

11..A soldering iron comprising ahollow heat retaining body of relatively 'large mass, an elongated soldering tip of relatively small mass reeiprocable therein and heated thereby,

resilient locking means for normally fixing the position ofthe tip, and manuallyY operable means for opposingfand releasing the resilient locking means in `order topermit variation of the position ofthe tip for temperature control. y l Y 12. A solderingfiron comprising hollow heat retaining body of relatively `lafpe mass,

mass projecting from the other end thereof, the tip being inserted in and reciprocable in the body for a substantial distance in order to regulate the temperature of the tip, a control rod secured to said tip and extending through the body to the handle, and control means at the handle cooperating with said control rod for determining the position of the tip.

14. A soldering iron comprising an axially bored heat retaining body of relatively large mass, a handle secured to one end thereof, an elongated soldering tip of relatively small mass projecting from the other end thereof, the tip being inserted in and reciprocable in the body for a substantial distance in order to regulate the temperature of the tip, a control rod secured to said tipand extending through the body to the handle, and means at said handle and operable upon said control rod for moving the rod and with it the tip.

15. A soldering iron comprising a hollow heat retaining body of relatively large mass, a .soldering tip of relatively small mass arranged movably within the body in order to permit of control of the temperature of the tip, the outer portion of said soldering tip being made of a good heat conducting material, and the inner end of said soldering tip being made of a poor heat conductor.

16. A soldering iron comprising a hollow heat retaining body of relatively large mass, a heating element associated therewith, an elongated soldering tip of relatively small mass the inner end of which is longitudinally reciprocable in the body in order to permit of control of the temperature of the tip, the outer portion of said reciprocable soldering tip being made of a good heat conducting material and the inner end of said soldering tip being made of a poor heat conductor, said poor heat conductor operating to minimize heatk transfer from the large mass to the soldering tip when the soldering tip is moved outwardly relative to the body, thereby reducing heat radiation and increasing the temperature ofthe body in order to insure a rapid rise in temperature of the tip when the tip is so moved into the body as to bring the body into direct heat transfer relation with the portion of the tip having good heat conductivity.

17. A soldering iron comprising a hollow heat retaining body of relatively large mass, an elongated soldering tip of relatively small mass the inner end of which is freely longitudinally reciprocable within the large body, and control means at the handle of said iron f for readily causing movement ofthe tip outwardly of the body in order to reduce the temperature of the tip, so that the temperature of body is automatically increased when Vthe tip is thus moved outwardly in order to thereby insure a rapid rise in temperature 

